A Study on the Characteristics of Fuel Consumption and Emissions of Diesel Vehicles Using Engine Coolant Flow Rate On/Off Control

엔진 냉각수 유량 단속에 의한 디젤 차량의 연비 및 배기가스 특성 연구

  • Kim, Sung Chul (Green Car Powertrain R&D Division, Korea Automotive Technology Institute)
  • 김성철 (자동차부품연구원 그린카파워트레인연구본부)
  • Received : 2013.02.08
  • Accepted : 2013.05.09
  • Published : 2013.05.31


The use of the electromagnetic clutch water pump for internal combustion engine vehicles saves fuel and leads to a reduction in emissions. The clutch water pump allows the engine cooling system to select the optimum operation condition by using coolant flow rate on/off control. This study investigated the characteristics of fuel consumption and emissions of the diesel engine cooling system using the clutch water pump. The electromagnetic clutch operation reduced by about 49% of engine warm up period at idle condition and controlled the optimum high coolant temperature at driving condition. Therefore, fuel consumption was enhanced by about 5%, and emissions such as HC, CO and $CO_2$ were also reduced to a certain degree even though NOx increased a little bit, compared to those of the conventional water pump under NEDC mode which represents the real driving pattern.


Water pump;Electromagnetic clutch;Fuel consumption;Emission;Warm-up;NEDC


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